A novel three-layer frame was developed to enable scalable phased-array coils. The geometry of the three-layer frame allows a single 12-element tile to dock with up to four identical tiles. When adjacent tiles are docked, the overlap of coils in adjacent tiles is identical to the coil overlap within a tile. Two phased-arrays setups using 12-element tiles and integrated balun coil technology were constructed. The first contained two separate tiles and the second had two interconnected tiles. The phased-array coils were evaluated with phantom imaging experiments and with multiple in-vivo experiments.